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2 which collectively divert clean water away from the disturbed area on either side of the North <br />Decline Road. A second inspection was conducted on February 24, 2014 by Mike Boulay of the <br />Division and Tonya Hammond representing SCC to complete those areas that were not inspected in <br />October. The West Diversion Ditch No. 1 and the East Diversion Ditches No.'s 1 & 2 are all <br />constructed as designed and stable with adequate depth and freeboard (see Photograph No.'s 2, 3 and <br />4). <br />Also inspected for a second time with the SL -8 evaluation were the North Decline permanent drainage <br />channel and reclaimed Pond 7. The North Decline permanent drainage channel is designed to the <br />100 -yr, 24-hour precipitation event for that locale. The design includes two upper sections requiring <br />riprap. Section 1 has a design slope of 0.075 and d50 riprap =10.2 inch (12 inch required), and Section <br />2 has a design slope of 0.025 and d50 riprap = 4.1 inch (6 inch required). These sections were <br />inspected to verify the riprap size and location and an inclinometer was used to field verify the slopes. <br />The riprap size is larger than required in both sections and the slopes were verified as follows: Section <br />1— 8% (Photograph No. 5) and Section 2 — 2% (Photograph No. 6) which closely matches the design. <br />The lower portion of the permanent channel is void of vegetation, with exception of a significant <br />Tamarisk infestation (see Photograph No. 7). Tamarisk is presently listed on Mesa County's noxious <br />weed list. The designs for the East and West Diversion ditches and the North Decline Permanent <br />Channel are given in Volume III of the PAP on pages NDEC-4 through NDEC-13. All of these <br />permanent drainage channel features are shown on Exhibit 12C of the PAP. Reclaimed Pond 7 is <br />stable with no erosion or instability but lacks desirable vegetative cover (Photograph No. 8). <br />Based on our inspections and evaluation of the SL -8 bond release application, Phase I bond release is <br />proposed for all areas requested for Phase I listed on Attachment 2. The location of reclaimed <br />Sedimentation Pond 7 have been carefully evaluated and will be excluded from full Phase III bond <br />release as described in greater detail below. <br />North Decline- Permanent Channel <br />Following the September 2013 inspection and prior to the SL -8 bond release inspection, SCC agreed <br />to remove sediment and repair rip rap in the main permanent diversion ditch that flows to the north <br />towards Interstate 70. SCC did clean a significant amount of the sediment that accumulated during <br />the heavy rainfall and storms that passed through the area prior to the September inspection depositing <br />much of the sediment in the main channel. Sediment that accumulated in the channel was used to <br />build up the ditch berms on both sides of the channel. The berms are devoid of vegetation; this is <br />because they were only recently seeded following the ditch repair that was required after the <br />August/September storm events. Photograph No. 9 shows the lower section of the main permanent <br />diversion channel at the North Decline after sediment cleanup and repair. <br />Designs of the permanent channel call for 12 inch rip rap or 6 inch rip rap based on slope in a small <br />section in the upper portions of this ditch. The North Decline permanent channel reestablishment <br />calculations are given in the PAP in Volume 3 Appendix 13-2, pages NDEC-11 through 13. Upon <br />follow up inspection in February, 2014, the Division determined that rip rap was placed accordingly <br />in the channel and verified that the channel received Phase I bond release back in August 2003 with <br />SL -2. <br />Page 11 <br />